The semiconductor industry has experienced rapid growth due to continuous improvement in the integration density of various electronic components (i.e., transistors, diodes, resistors, capacitors, etc.). For the most part, the improvement in integration density has come from gradual reductions in minimum feature size, which allows more of the smaller components to be integrated into a given area. These smaller electronic components also require smaller packages that utilize less area than previous packages. Some smaller types of packages for semiconductor components include quad flat packages (QFPs), pin grid array (PGA) packages, ball grid array (BGA) packages, and so on.
Currently, integrated fan-out packages are becoming increasingly popular for their compactness. How to reduce fabrication costs of the integrated fan-out packages are important issues.